Even though Apple’s (AAPL) highly anticipated next-generation iPhone is on the horizon, the company’s iPhone 4 and 4S are still expected to sell exceptionally well through the end of the third quarter. According to Digitimes, shipments of current iPhone models are estimated to grow 10% to 15% during the quarter, an increase from the company’s second quarter results, which disappointed the Street. The publication notes that Apple supplier Wintek saw its revenues soar 60% in July, thanks in part to the Cupertino-based company’s increased touch panel orders for its iPhone 4S. In addition, various brick and mortar retailers, along with several carriers, have also begun to discount the price of older iPhone models, which should help sales increase during this quarter.